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Abstract:

A liquid crystal display device includes a display portion having a first
substrate, a second substrate opposing to the first substrate, a liquid
crystal layer held between the first and second substrates, and a
plurality of pixels arranged in a delta shape. A plurality of pixel
electrodes are respectively connected to signal lines extending in a
first direction via a switch. The switch is controlled by scanning lines
extending in a second direction which orthogonally crosses the first
direction. The signal lines extend in a space between the pixel
electrodes in a meandering shape in the second direction, and two kinds
of color pixels are connected with a common signal line in turn via the
pixel switch.

Claims:

1. A liquid crystal display device comprising:a display portion including
a first substrate, a second substrate opposing to the first substrate, a
liquid crystal layer held between the first and second substrates, and a
plurality of pixels arranged in a delta shape;the first substrate
including;a plurality of pixel electrodes respectively arranged in the
pixels,scanning lines extending in a first direction,signal lines
extending in a second direction crossing orthogonally with the first
direction, andpixel switches arranged around the crossing area of the
scanning lines with the signal lines, corresponding to respective pixel
electrodes, and;wherein the signal lines extend in a space between the
pixel electrodes in a meandering shape in a second direction, and two
kinds of color pixels are connected with a common signal line by turn via
the pixel switch.

2. The liquid crystal display device according to claim 1, further
comprising a driving circuit to drive the scan lines and the signal
lines, wherein the driving circuit includes a polarity inversion circuit
to inverse respective polarity of signals supplied to the pixel
electrodes arranged in the first direction one by one base and to inverse
respective polarity of the signals supplied to the pixel electrodes from
a common signal line every two or more pixel electrodes arranged
adjacently along the common signal line.

3. The liquid crystal display device according to claim 2, further
comprising a plurality of auxiliary capacitance lines extending in the
first direction in parallel with the scan line, wherein the pixel
electrode includes auxiliary capacitance generated by a voltage applied
between the pixel electrode and the auxiliary capacitance line, and the
respective auxiliary capacitance lines are coupled with the pixel
electrode into which one of a signal of positive polarity and a signal of
negative polarity is written through the auxiliary capacitance.

4. The liquid crystal display device according to claim 3, wherein the
auxiliary capacitance lines include first and second capacitance lines
arranged in turn, and signals having positive and negative polarities are
supplied to the first and second capacitance lines respectively.

5. The liquid crystal display device according to claim 1, further
comprising;a driving circuit to drive the scan lines and the signal
lines,a selection circuit to distribute an output signal outputted from
an output terminal of the signal line driving circuit to two or more
signal lines in a time sharing, the selection circuit being structured so
as to distribute the output signals from its output terminal to
respective pixel signal lines to supply signals with the same color and
the same polarity to the pixel electrodes, anda control circuit to
control the driving circuit and the selection circuit, the control
circuit including a selection driving control circuit to control the
driving circuit and the selection circuit so as to supply the same signal
to at least one of two or more signal lines two or more times within 1
horizontal scan time.

6. The liquid crystal display device according to claim 1, further
comprising;a driving circuit to drive the scan lines and the signal
lines,a selection circuit to distribute an output signal outputted from
an output terminal of the driving circuit to two or more signal lines in
a time sharing, the selection circuit being structured so as to
distribute the output signals from its output terminal to respective
signal lines to supply signals with the same color and the same polarity
to the pixel electrodes, anda control circuit to control the driving
circuit and the selection circuit, the control circuit including a
selection driving control circuit to control the driving circuit and the
selection circuit so as to supply a reset signal to the pixels at the
first period and picture signals at the second period within 1 horizontal
scan time.

7. The liquid crystal display device according to claim 6, wherein the
selection driving control circuit controls the driving circuit and the
selection circuit so as to supply the same signal to at least one of two
or more signal lines two or more times within 1 horizontal scan time.

8. The liquid crystal display device according to claim 6,wherein the
liquid crystal layer includes an OCB mode liquid crystal material in
which the liquid crystal is transferred to a bend alignment state from a
spray alignment state, a reverse transference from the bend alignment
state to the spray alignment state is prevented by periodically applying
the reset signal corresponding to a black display to the liquid crystal
layer.

9. A liquid crystal display device comprising:a display portion including
a first substrate, a second substrate opposing to the first substrate, a
liquid crystal layer held between the first and second substrates, and a
plurality of pixels to display red, green and blue colors arranged in a
delta shape;the first substrate including;(a) a plurality of pixel
electrodes respectively arranged in the pixels,(b) scanning lines
extending in a first direction, the signal lines extending in a space
between the pixel electrodes in a meandering shape in a second
direction,(c) signal lines extending in a second direction crossing
orthogonally with the first direction, and(c) pixel switches arranged
around the crossing area of the scanning lines with the signal lines,
corresponding to respective pixel electrodes,a signal line driving
circuit and a scan line driving circuit to drive the scan lines and
signal lines respectively,a selection circuit to distribute an output
signal outputted from an output terminal of the signal line driving
circuit to two or more signal lines in a time sharing, the selection
circuit being structured so as to distribute the output signals from the
output terminal to respective signal lines to supply the signals with the
same color and the same polarity to the pixel electrode,a polarity
inversion circuit to inverse respective polarity of signals supplied to
the pixel electrodes arranged in the first direction one by one base and
to inverse respective polarity of the signals supplied to the pixel
electrodes from a common signal line every two or more pixel electrodes
arranged adjacently along the common signal line, anda plurality of
auxiliary capacitance lines extending in the first direction, wherein the
pixel electrode includes auxiliary capacitance generated by a voltage
applied between the pixel electrode and the auxiliary capacitance line,
and the auxiliary capacitance line is coupled with the pixel electrode
into which one of a signal of positive polarity and a signal of negative
polarity through the auxiliary capacitance is written.

10. The liquid crystal display device according to claim 9, further
comprising;a control circuit to control the selection circuit so as to
supply a reset signal to the pixels at the first period and picture
signals at the second period within 1 horizontal scan time.

11. The liquid crystal display device according to claim 9, further
comprising, a selection driving control circuit to control the selection
circuit so as to supply the same signal to at least one of two or more
signal lines two or more times within 1 horizontal scan time.

12. The liquid crystal display device according to claim 10, wherein the
liquid crystal layer includes an OCB mode liquid crystal material in
which the liquid crystal is transferred to a bend alignment state from a
spray alignment state by applying a voltage.

13. The liquid crystal display device according to claim 12, wherein a
reverse transference from the bend alignment state to the spray alignment
state is prevented by periodically applying the reset signal
corresponding to a black display to the liquid crystal layer.

14. The liquid crystal display device according to claim 13, wherein the
period when the reset signal is divided into three sub-periods, and
respectively supplied to signal lines connected to the red pixel, the
green pixel and the blue pixel.

15. The liquid crystal display device according to claim 14, wherein the
voltage values of the respective reset signals is slightly different each
other.

16. The liquid crystal display device according to claim 9, wherein the
auxiliary capacitance lines include first and second capacitance lines
arranged in turn, and signals having positive and negative polarities are
supplied to the first and second capacitance lines respectively.

17. A method of driving a liquid crystal display device having a display
portion including a first substrate, a second substrate opposing to the
first substrate, a liquid crystal layer held between the first and second
substrates, and a plurality of pixels arranged in a delta shape; the
first substrate including, a plurality of pixel electrodes respectively
arranged in the pixels, scanning lines extending in a first direction,
signal lines extending in a second direction crossing orthogonally with
the first direction, and pixel switches arranged around the crossing area
of the scanning lines and the signal lines, corresponding to respective
pixel electrodes, the method comprising the steps of:forming the signal
lines extending in a space between the pixel electrodes in a meandering
shape in a second direction, and two kinds of color pixels connected with
a common signal line by turn via the pixel switch,turning on the pixel
switch by the scanning line sequentially driven under control of the
scanning line driving circuit,writing a signal into the pixels via the
pixel switch from the signal lines under control of the signal line
driving circuit,inversing respective polarity of signals supplied to the
pixel electrodes arranged in the first direction one by one base and
respective polarity of the signals supplied to the pixel electrodes from
a common signal line every two or more pixel electrodes arranged
adjacently.

18. The method of driving a liquid crystal display device according to
claim 17 further having a selection circuit to distribute output signals
from the output terminal of the signal line driving circuit to respective
signal lines to supply signals with the same color and the same polarity
to the pixel electrodes, and the signal lines including a first signal
line connected with the output terminal through a first switch, a second
signal line connected with the output terminal through a second switch, a
third signal line connected with the output terminal through a third
switch, the method comprising the steps of:turning on the first, second
and the third switches by controlling the selection circuit within 1
horizontal scan time,turning off the first switch while the second and
third switches are turned on,turning off the first and second witches
while the third switch is turned on, andturning off the first, second and
third witches.

19. The method of driving a liquid crystal display device according to
claim 18 further having a selection circuit to distribute output signals
from the output terminal of the signal line driving circuit to supply
signals with the same polarity to the pixel electrodes, the signal line
including a first signal line connected with the output terminal through
a first switch, a second signal line connected with the output terminal
through a second switch, and a third signal line connected with the
output terminal through a third switch, and the method further comprising
the steps;supplying a reset signal to the signal lines from the output
terminal of the signal driving circuit so as to distribute the reset
signal by turning on the first, second and third switches at a first
period within 1 horizontal scan time, andsupplying picture signals to the
signal lines from the output terminal of the signal driving circuit so as
to sequentially distribute the picture signals in a predetermined order
by turning on the first, second and third switches at a second period
within 1 horizontal scan time.

20. A method of driving a liquid crystal display device according to claim
19;wherein the liquid crystal layer includes an OCB mode liquid crystal
material in which the liquid crystal is transferred to a bend alignment
state from a spray alignment state, a reverse transference from the bend
alignment state to the spray alignment state is prevented by periodically
applying the reset signal corresponding to a black display to the liquid
crystal layer.

Description:

CROSS-REFERENCE TO RELATED APPLICATION

[0001]This application is based upon and claims the benefit of priority
from prior Japanese Patent Application No. 2009-118613, filed May 15,
2009, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002]1. Field of the Invention

[0003]The present invention relates to a liquid crystal display device,
and more particularly to a liquid crystal display device using a delta
arrangement of pixels and a method of driving the same.

[0004]2. Description of the Related Art

[0005]The liquid crystal display device includes a pair of substrates, a
liquid crystal layer held between the pair of substrates, and a display
portion formed of a plurality of display pixels. In a case of a color
type liquid crystal display device, each of the plurality of display
pixels includes some kinds of color pixels.

[0006]Namely, when each of the display pixels is formed of a red pixel to
display red color, a green pixel to display green color, and a blue pixel
to display blue color, an arrangement method of pixels may be used, in
which the red pixel, the blue pixel and the green pixel are arranged in a
stripe shape so as to line every same color pixels.

[0007]When arranging the pixels in a stripe shape for every same color,
the pixels that are arranged at the edge of the display portion are same
color pixels in a direction where a stripe-like line extends. Therefore,
a line of the single color might be recognized visually at the edge of
the display portion. Furthermore, cracks between adjacent lines of the
pixels arranged in a line may be also recognized visually in the stripe
shape.

[0008]Other pixel arrangement (hereafter referred to a delta arrangement)
which shifts each of adjacent pixels arranged in a row direction to 1.5
pixel span of each color pixel with respect to adjoining row lines of
pixels is proposed in a Japanese laid open patent application No.
2000-194017. According to the delta arrangement, since the pixels of the
same color are not arranged in a line at the end of a display portion,
the line of a single color is not recognized visually at the end of the
display portion. Furthermore, since the pixels are not lined in a column
direction, the edge of the display portion is not recognized visually in
a line shape, which prevents a decrease of the display quality.

[0009]Generally, the liquid crystal display device adopts an alternating
electric field driving, that is, a polarity of a voltage applied to the
liquid crystal layer is inversed in every selected scan line as
countermeasure against flicker. However, if only one of the polarity
changes in every selected scan line and every selected signal line is
adopted, the flicker may be generated in a direction in which scan lines
or signal lines extend. Accordingly, in a high quality liquid crystal
display device, a dot inversion driving in which the polarity of the
voltage applied to the liquid crystal layer is inversed both in every
selected scan line and every selected signal line.

[0010]On the other hand, a capacitive coupling driving (CC driving) is
proposed to decrease an amplitude of signal voltages. In the capacitive
coupling driving, a predetermined pixel voltage is obtained by adding an
auxiliary capacitance signal to a pixel electrode through an auxiliary
capacitance. If the capacitance values of the auxiliary capacitance and a
pixel capacitance are set substantially equal, the amplitude of the
signal voltage is reduced by half.

[0011]On the other hand, a black insertion driving is known to prevent a
smudgy display, that is, a scan for the black insertion driving and a
scan for writing image signals into the pixel are conducted within one
frame scan period. Furthermore, a selection driving is used to lower cost
by reducing number of driver circuits and peripheral wiring area to
achieve a narrow frame display.

[0012]In the case of the delta pixel arrangement is used, above described
CC driving, the capacitive coupling dot inversion driving (CCDI driving),
the selection driving, and the black insertion driving may be also
applied to achieve the low power consumption and the narrow frame
display. Here, especially, the CC driving applicable to the dot inversion
driving is called a CCDI driving.

[0013]However, if the delta arrangement described in the laid open patent
application is adopted, a pattern of the signal wiring for supplying
picture signals to the plurality pixels in the liquid crystal display
device becomes complicated, which results in difficulty of achieving the
low power consumption and the narrow frame display by using the delta
arrangement.

[0014]The present invention is accomplished in light of the
above-mentioned circumstances. The purposes of the present invention is
to provide a high quality liquid crystal display device and a method
driving the same, using a delta arrangement capable of achieving a low
power consumption and a narrow frame display device.

BRIEF SUMMARY OF THE INVENTION

[0015]The present invention has been made to address the above mentioned
problems. One object of this invention is to provide a liquid crystal
display device capable of reducing power consumption and preventing
degradation of the display quality.

[0016]Thus, according to one aspect of the invention, there is provided a
liquid crystal display device comprising: a display portion including a
first substrate, a second substrate opposing to the first substrate, a
liquid crystal layer held between the first and second substrates, and a
plurality of pixels arranged in a delta shape; the first substrate
including; a plurality of pixel electrodes respectively arranged in the
pixels, scanning lines extending in a first direction, signal lines
extending in a second direction crossing orthogonally with the first
direction, and pixel switches arranged around the crossing area of the
scanning lines and with signal lines, corresponding to respective pixel
electrodes, and; wherein the signal lines extend in a space between the
pixel electrodes in a meandering shape in a second direction, and two
kinds of color pixels are connected with a common signal line by turn via
the pixel switch.

[0017]According to another aspect of the invention, there is provided a
method of driving a liquid crystal display device having a display
portion including a first substrate, a second substrate opposing to the
first substrate, a liquid crystal layer held between the first and second
substrates, and a plurality of pixels arranged in a delta shape; the
first substrate including, a plurality of pixel electrodes respectively
arranged in the pixels, scanning lines extending in a first direction,
signal lines extending in a second direction crossing orthogonally with
the first direction, and pixel switches arranged around the crossing area
of the scanning lines and the signal lines, corresponding to respective
pixel electrodes, the method comprising the steps of: forming the signal
lines extending in a space between the pixel electrodes in a meandering
shape in a second direction, and two kinds of color pixels connected with
a common signal line in turn via the pixel switch, turning on the pixel
switch by the scanning line sequentially driven under control of a
scanning line driving circuit, writing a signal into the pixels via the
pixel switch from the signal lines under control of a signal line driving
circuit, inversing respective polarity of signals supplied to the pixel
electrode arranged in the first direction one by one base and respective
polarity of the signals supplied to the pixel electrodes from a common
signal line every two or more pixel electrodes arranged adjacently.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]The accompanying drawings, which are incorporated in and constitute
a part of the specification, illustrate embodiments of the invention, and
together with the general description given above and the detailed
description of the embodiments given below, serve to explain the
principles of the invention.

[0019]FIG. 1 is a diagram showing a basic structure of a liquid crystal
display device according to the present invention.

[0020]FIG. 2 is a timing chart showing a driving operation of the liquid
crystal display device shown in FIG. 1.

[0021]FIG. 3 is a pattern layout of pixels using a delta arrangement of
the liquid crystal display device in a prior art.

[0022]FIG. 4 is a pattern layout of the pixels using the delta arrangement
of the liquid crystal display device according to a first embodiment of
the present invention.

[0023]FIG. 5 is a pattern layout of the pixels using the delta arrangement
and an alternating driving operation to supply picture signals to pixel
electrodes of the liquid crystal display device shown in FIG. 4.

[0024]FIG. 6 is a pattern layout of the pixels for a capacitive coupling
driving using the delta arrangement and an alternating driving to supply
picture signals to the pixel electrodes of the liquid crystal display
device shown in FIG. 4 according to a second embodiment of the present
invention.

[0025]FIG. 7 is a pattern layout of the pixels shown in FIG. 6 with
auxiliary capacitances connected to the pixel electrode to show a
capacitive coupling driving.

[0026]FIG. 8 is a timing chart showing the driving operation by the
capacitive coupling driving of the liquid crystal display device shown in
FIG. 7.

[0027]FIG. 9 is a pattern layout of the pixels in case of coupling the
auxiliary capacitance to the pixel electrode shown in FIG. 6 according to
a third embodiment of the present invention.

[0028]FIG. 10 is a timing chart showing a driving operation by the
capacitive coupling driving of the liquid crystal display device shown in
FIG. 9.

[0029]FIG. 11 shows a display portion and a selection circuit in case of
conducting an alternating driving operation and a selection driving
operation using the pattern layout of pixels shown in FIG. 6 according to
a fourth embodiment of the present invention.

[0031]FIG. 13 shows the display portion and the selection circuit in case
of conducting the alternating driving operation and the selection driving
operation using the pattern layout of pixels shown in FIG. 6 according to
a fifth embodiment of the present invention.

[0032]FIG. 14 is a timing chart showing wave forms of the signal lines in
case of conducting the selection driving operation shown in FIG. 13.

[0033]FIG. 15 is a timing chart showing wave forms of the scan lines in
case of conducting the selection driving operation shown in FIG. 13.

DETAILED DESCRIPTION OF THE INVENTION

[0034]A liquid crystal display device, according to an exemplary
embodiment of the present invention, in particular, a liquid crystal
display device and a method of driving the same using a delta pixel
arrangement will be explained.

[0035]Hereafter, a basic structure of a liquid crystal display device and
a driving method of the liquid crystal display device according to the
present invention is explained referring to FIG. 1. The Liquid crystal
display device includes a liquid crystal display panel PNL having a
display portion DYP formed of a plurality of display pixels PX, a back
light BL to illuminate the liquid crystal display portion DYP, and a
control circuit CTR to control the liquid crystal display panel PNL and
the back light BL.

[0036]The liquid crystal display device panel PNL has an array substrate
(not shown) and an opposite substrate (not shown), and a liquid crystal
layer held between the array substrate and the opposite substrate. In the
liquid crystal display device according to this embodiment, a delta pixel
arrangement is adopted.

[0037]The liquid crystal display device according to this embodiment is a
color type liquid crystal display device, and each of the display pixels
PXs includes a plurality of color pixels. The liquid crystal display
device shown in FIG. 1 includes a red pixel PXR to display red color, a
green pixel PXG to display green color, and a blue pixel PXB to display
blue color.

[0038]The plurality of display pixel PXs include a plurality of pixels
arranged in a first D1 direction (row direction), in a predetermined
order. Each of the color pixels in a row line is arranged so as to shift
by 1.5 pixel span to the color pixels arranged in the adjoining row lines
in the row direction.

[0039]The array substrate includes a transparent insulation substrate,
such as glass, for example. A plurality of pixel electrodes corresponding
to the respective display pixels PXs are arranged on the transparent
insulation substrate. A plurality of scanning lines G (G1˜Gm) are
arranged along with the row line in which the pixel electrodes PE are
arranged. Furthermore, a plurality of signal lines S (S1˜Sn) are
arranged in a space between adjacent pixel electrodes PE along the second
direction D2 in a zigzag style. A plurality of auxiliary capacitance
lines Cs (Cs0˜Csm-1) are arranged substantially in parallel with
the scan lines G, and a plurality of pixel switches SW0 are arranged near
the intersection area with the scan lines G and the signal lines S.

[0040]Each of the pixel switches SW0 includes a thin film transistor as a
switching element, for example. The respective gates of the pixel
switches SW0 are connected to the scanning lines G, and a source and
drain path is connected between the signal line S and the pixel electrode
PE. When each of the pixel switches SW0 is driven by the corresponding
scan line G, the switch SW0 becomes conductive between the pixel
electrode PE and the corresponding signal line S.

[0041]The liquid crystal panel PNL further includes a gate driver GD which
successively drives the plurality of scanning lines G1˜Gm one by
one, a source driver SD which outputs picture signals or non-picture
signals to each of the plurality of signal lines S1˜Sn in the
period when the respective pixel switches SW0 are selected by
corresponding scanning lines G, a Cs driver CsD which drives the
plurality of auxiliary capacitance lines Cs0˜Csm-1, and a selection
circuit MPX which distributes the signals outputted from the source
driver SD to the plurality of signal lines S.

[0042]Some external ICs are used to form the gate driver GD, the source
driver SD, and the Cs driver CsD or the drivers may be built on the array
substrate, as built-in circuits. The gate driver GD, the source driver
SD, and the selection circuit MPX are arranged in a peripheral portion of
the display portion DYP, and are controlled by the control circuit CTR.

[0043]The opposite substrate includes a color filter (not shown) formed of
a red colored resin, a green colored resin and a blue colored resin on
the transparent insulation substrate, such as glass. The opposite
substrate further includes an opposite electrode (not shown) which
counters the plurality of pixel electrodes, and is arranged on the color
filter.

[0044]Each of the pixel electrodes PE and the opposite electrode are
respectively formed of a transparent material such as ITO and covered
with a pair of alignment films in which a rubbing processing is carried
out (not shown) in a parallel direction each other respectively. Each of
the pixel electrodes PE and the opposite electrode constitute a display
pixel PX with a pixel field which is a part of the liquid crystal layer
controlled by the electric field between the pixel electrode PE and the
opposite electrode.

[0045]The plurality of color pixels are classified according to the colors
of the layers arranged in the respective color pixels. The red pixel PXR
contains a red color layer. The green pixel PXG contains a green color
layer. Similarly, the blue pixel PXB contains a blue color layer.

[0046]Each of the display pixel PXs has a liquid crystal capacitance (not
shown) formed by the liquid crystal layer held between the pixel
electrode PE and the opposite electrode. The liquid crystal capacitance
value is decided by a specific inductive capacitance of liquid crystal
material, a pixel electrode area, and a cell gap between the pixel
electrode PE and the opposite electrode.

[0047]A voltage (hereafter referred as a source voltage) supplied to the
signal line S by the source driver SD is supplied to the pixel electrode
PE of the display pixel PX through a corresponding pixel switch SW0. A
potential difference between a voltage (pixel potential) impressed to the
pixel electrode PE and a opposite common voltage Vcom impressed to the
opposite common electrode is maintained by the liquid crystal
capacitance.

[0048]An auxiliary capacitance Cst is formed by a portion of the pixel
electrode PE laminated via an insulating film and the auxiliary
capacitance line Cs (Cs0˜Csm-1) extending in parallel with the
scanning line G. The auxiliary capacitance Cst is combined with the
liquid crystal capacitance in a holding period after writing the picture
signals into the pixel electrode PE.

[0049]A control circuit CTR outputs a control signal CTG generated based
on a synchronized signal inputted from an outside signal source SS to the
gate driver GD. Similarly, the control circuit CTR outputs a control
signal CTS generated based on the synchronized signal inputted from the
outside signal source SS, picture signals or a reverse transference
prevention signal for a black insertion, inputted from the outside signal
source SS to the source driver SD. The control circuit CTR also outputs
the opposite common voltage Vcom impressed to the opposite electrode of
the opposite substrate.

[0050]The source driver SD outputs a plurality of picture signals or the
reverse transference prevention signals in parallel. The outputted
signals from the source driver SD are distributed to the signal lines
S1˜Sn by the selection circuit MPX.

[0051]The selection circuit MPX includes a first switch SW1 having ON and
OFF states controlled by a first control signal ASW1, a second switch SW2
controlled by a second control signal ASW2, and a third switch SW3
controlled by a third control signal ASW3. The signal outputted from the
source driver SD is supplied to a corresponding signal line S via either
one of the first switch SW1, the second switch SW2 and the third switch
SW3.

[0052]According to this embodiment, the CCDI driving is adopted. In the
CCDI driving, after signals are written in the pixels from the selected
signal line S, a superposed voltage by capacitive coupling is applied to
the potential of the pixel electrode PE, and an increased amplitude
effect is acquired.

[0053]Specifically, the auxiliary capacitance Cst is formed between the
auxiliary capacitance line Cs extending in the first direction D1 and the
pixel electrode PE, by applying a voltage from the Cs driver CsD as shown
in FIG. 2.

[0054]Immediately after the scan lines G are selected, the potential of
the auxiliary capacitance line Cs is changed from a positive potential
Vc(+) to a negative potential Vc(-) or from the negative potential Vc(-)
to the positive potential Vc(+). Consequently, a larger voltage amplitude
to hold the pixel than a range (picture signal amplitude) of the signal
voltage given to the pixel electrode PE from the signal line S can be
obtained by applying a coupling voltage through the coupling capacitance
to the pixel electrode PE.

[0055]According to the CC driving, the source driver SD with small voltage
amplitude can be used, and merits of driver cost reduction and power
consumption reduction are obtained. If the auxiliary capacitance line Cs
is commonly connected to respective auxiliary capacitances Cst of the
pixels lined in one selected scanning line G, the polarity of the
superimposed voltage to the pixel electrodes PE becomes the same for all
the pixels in one row. Therefore, the CC driving can not be applied to
the dot inversion driving, in which positive and negative polarities of
the pixels selected by a common scanning line G are mixed within a row
line.

[0056]In case of applying the CC driving to the dot inversion driving, it
is necessary to prepare a pair of auxiliary capacitance lines Cs to
generate, for example, an auxiliary capacitance Cst for the pixel
electrodes PE to which a positive signal is applied using an upper side
auxiliary capacitance line Cs, and another auxiliary capacitance Cst for
the pixel electrodes PE to which a negative signal is applied using a
lower side auxiliary capacitance line Cs. Here, the pair of auxiliary
capacitance lines Cs of upper and lower sides are illustrated in parallel
with scan lines G so as to interleave the pixel electrode PE arranged in
the row direction in FIG. 1.

[0057]Therefore, in the liquid crystal display shown in FIG. 1, two types
of pixels PX selected by a common scanning line G exist in mixture.
Namely, in one type pixel PX, the auxiliary capacitance Cst is formed
between the upper auxiliary capacitance line Cs and the pixel electrode
PE, and in another type of pixel, the auxiliary capacitance Cst is formed
between the lower auxiliary capacitance line Cs and the pixel electrode
PE.

[0058]In the CC driving (line reversal driving or frame reversal driving)
in which all the pixels PX in one row line have the same polarity, an
undesirable horizontal cross talk generates due to coupling between the
signal line S and the opposite electrode or the auxiliary capacitance
line Cs. However, in the CCDI driving, since positive/negative polarities
are mixed, the coupling is set off by positive/negative polarities, and
the generation of the horizontal cross talk is suppressed, which results
in the prevention of the cross talk.

[0059]In the line reversal driving, when the opposite electrode potential
shifts, a line flicker may be seen. However, in the dot inversion
driving, even if the opposite electrode potential shifts, the line
flicker cannot be easily seen.

[0060]In the liquid crystal display device according to this embodiment, a
selection driving which uses a selection circuit MPX is adopted. The
selection circuit MPX is provided with a multiplexer. The selection
driving distributes output signals from one output terminal SS (shown in
FIGS. 11 and 13) of the source driver SD to the plurality of signal lines
S in time sharing.

[0061]In the selection circuit MPX of FIG. 1, the respective first switch
SW1, second switch SW2, and third switch SW3 made of a thin film
transistor (TFT: Thin Film Transistor) are inserted between the output
terminal SS of the source driver SD and each of the signal lines S.
ON/(connection) and OFF/(non-connection) of the TFT are controlled by a
potential of the control signal lines ASW (ASW1˜ASW3) extending to
the selection circuit MPX from the control circuit CTR.

[0062]In the liquid crystal display device shown in FIG. 1, a method
(three line selection method) is adopted, in which output signals from
the output terminal SS of the source driver SD are distributed to three
signal lines S. By the selection driving using the selection circuit MPX,
the cost reduction due to number reduction of elements constituting the
source driver SD is achieved. Furthermore, a narrow picture frame by
reducing wiring area in the circumference of the display portion DYP is
also achieved.

[0063]FIG. 3 is a pattern layout of the pixels using the delta arrangement
of the liquid crystal display device in a prior art. An arrangement of
the pixel switch SW0 in the pixels PX is explained, in which a delta
arrangement is formed. Each signal line S is connected to the respective
color pixels of the same color. A signal line Sa is connected to green
pixels PXGA and PXGB via the pixel switches SW0 respectively. In this
case, when supplying a signal with the same polarity, for example, to the
green pixels PXGA and PXGB, the time to charge the signal line Sa is
shortened, and shortage of write-in charge is improved.

[0064]However, as shown in FIG. 3, when color pixels PX of the same color
are connected to the same signal line S, largeness of the potential held
at the green pixel PXGA and the green pixel PXGB may differ due to the
difference in the largeness of stray capacitance therebetween, which
results in a decrease in the display quality.

[0065]That is, the pixel electrode PE of the green pixel PXGA is arranged
between the signal line Sa and a signal line Sa-1. In a timing when a
scanning line Gb-1 is selected, a signal supplied to a pixel electrode PE
of a red pixel PXR arranged adjacent to the green pixel PXGA is supplied
to the signal line Sa-1. At this time, stray capacitance arises between
the pixel electrode PE of the green pixel PXGA, and the signal line Sa-1.
The stray capacitance is combined with the pixel capacitance and is held
together. Similarly, in the green pixel PXGB, stray capacitance arises
between the pixel electrode PE and an adjacent signal line Sa+1, and is
combined with the pixel capacitance, thereby this capacitance is also
held together.

[0066]When the largeness of the stray capacitance combined with the pixel
capacitance of the green pixel PXGA differs from that of the stray
capacitance combined with the pixel capacitance of the green pixel PXGB,
the pictures displayed by the green pixels PXGB and PXGA also differ from
each other, and display quality is decreased. That is, a luminosity of
the green pixel PXG arranged at even-numbered row lines differs from that
of the green pixel PXG arranged at odd-numbered row lines, and horizontal
stripes of light and darkness may be recognized visually.

[0067]FIG. 4 is a pattern layout of the pixels using the delta arrangement
of the liquid crystal display device according to a first embodiment of
the present invention. In the liquid crystal display device shown in FIG.
4, in order to improve that the display device quality decreases as
mentioned above, the signal line S is connected with the pixel electrode
PE as follows. For example, a pixel electrode PE of a red pixel PXR and a
pixel electrode PE of a blue pixel PXB are respectively connected to a
common signal line Sa in turn via the switch SW0.

[0068]For example, the pixel electrode PE of the green pixel PXGA is
arranged between the signal line Sa and the signal line Sa-1. In the
timing when the scanning line Gb-1 is selected, a signal supplied to the
pixel electrode PE of the blue pixel PXB arranged next is supplied to the
signal line Sa. At this time, stray capacitance arises between the pixel
electrode PE of the green pixel PXGA and the signal line Sa, and is
combined with the pixel capacitance, and the stray capacitance is held
together.

[0069]Similarly, the pixel electrode PE of the green pixel PXGB is
arranged between a signal line Sa+1 and a signal line Sa+2. In a timing
when a scanning line Gb is selected, a signal supplied to a pixel
electrode PE of a blue pixel PXB arranged next is supplied to the signal
line Sa+2. At this time, stray capacitance arises between the picture the
electrode PE of the green pixel PXGB and the signal line Sa+2, and
combined with the pixel capacitance, and the stray capacitance is held
together.

[0070]Therefore, the largeness of the capacitance combined with the pixel
capacitance of the green pixel PXGA becomes substantially equal to that
combined with the pixel capacitance of the green pixel PXGB. Accordingly,
the deterioration of the display quality is suppressed.

[0071]Next, the polarity of the signal supplied to each of the pixel
electrodes PE is explained in the liquid crystal display device according
to this embodiment. Generally, if a direct-current (DC) bias is impressed
to the liquid crystal layer for a long time, the liquid crystal is
charged up, and which results in a problem such as printing phenomenon.
In order to prevent the printing phenomenon, the polarity of the applied
voltage to the display device is reversed for every frame so that the
average of direct-current ingredient of the voltage applied to the liquid
crystal layer is set to about 0 V.

[0072]However, if the polarity of the signals supplied to all the pixel
electrodes (frame inversion driving) is inversed simultaneously, the
difference between light and darkness arises for every frame, and a
flicker occurs. Then, some inversion driving methods are used, such as a
line inversion driving for every row lines, a column inversion driving
for every column lines, and a dot inversion driving to inverse the
polarity in checkers combining the line inversion driving and the column
line inversion driving.

[0073]Among these, since the signal supplied to the signal line S is
inversed during a signal holding time every 1 horizontal cycle, a DC
average value of the signal line potential is set to about 0 in the line
inversion driving and the dot inversion driving. Accordingly, even if
stray capacitance (Csd) is generated between the pixel electrode PE and
the signal line S, an undesirable picture such as a vertical cross talk,
is suppressed without giving excessive coupling voltage to the pixel
potential Vd.

[0074]On the other hand, in the frame inversion driving or the column
inversion driving, since the average value of the direct-current
ingredient of the signal line potential of a holding time is not about 0,
and may be dependent on a display condition of the other pixels arranged
in the same column line and in other row lines. Accordingly, if there is
stray capacitance (Csd), the holding voltage of the pixel electrode PE is
influenced by a display condition of the other pixels arranged in the
same column line and in other row lines, which results in the cross talk.

[0075]FIG. 5 is a pattern layout of the pixels using the delta arrangement
and the alternating driving operation to supply picture signals to the
pixel electrodes PE of the liquid crystal display device shown in FIG. 4.
In the liquid crystal display device according to this embodiment, the
dot inversion driving is adopted as a polarity-inversion method. The
polarity of the signal supplied to the pixel electrode PE is inversed
every 1 horizontal period (1H) as shown in FIG. 5.

[0076]Accordingly, the signals with a mutually different polarity are
supplied by turn to the pixel electrodes PE arranged adjacently in the
first direction D1. Furthermore, the signals with positive and negative
polarities are supplied to the pixel electrodes PE connected to a common
signal line S by turns respectively.

[0077]Thus, if the signals whose polarity are inversed by turns are
supplied to the pixel electrodes PE connected to the same signal line S,
the signal with the same polarity is supplied to the pixel electrode PE
of the blue pixel PXB connected to the signal line Sa, for example, in
one frame period. In FIG. 5, the signals with positive polarity are
supplied to the pixel electrodes PE of the blue pixels PXB connected to
the signal line Sa.

[0078]In the driving method shown in FIG. 5, a vertical cross talk in a
gray display is not generated. However, the vertical cross talk occurs by
a colored display, such as yellow. This cause is considered as follows.
For example, in the display of yellow, a signal corresponding to a white
display is supplied to the red pixel PXR, a signal corresponding to a
white display is supplied to the green pixel PXG, and a signal
corresponding to a black display is supplied to the blue pixel PXB.

[0079]The potential supplied to the signal line Sa at this time changes
from a potential corresponding to the black display of positive polarity
to a potential corresponding to the white display of negative polarity
during the holding period, and changes to the potential corresponding to
the black display of positive polarity again. The signal potential of
positive polarity always turns into the potential for the black display,
and the signal potential of negative polarity always turns into the
potential for the white display, therefore the average of direct-current
(DC) ingredient of the potential of the signal line Sa changes from about
0. Accordingly, a coupling voltage generated by stray capacitance between
the source and drain electrodes of the pixel switch SW0 is superposed to
the pixel electrode PE, and which results in the potential change of the
pixel electrode PE and further the vertical cross talk.

[0080]Then, the signal supplied to the pixel electrode PE is inversed
every 2 horizontal periods as shown in FIG. 6. FIG. 6 is a pattern layout
of the pixels for a capacitive coupling driving using the delta
arrangement and the alternating driving to supply picture signals to the
pixel electrode PE of the liquid crystal display device shown in FIG. 4
according to a second embodiment of the present invention.

[0081]The gate driver GD and the source driver SD controlled by the
control circuit CTR inverse the signals applied to the pixels PE arranged
in the first direction D1 for every pixel PX. Furthermore, the polarity
of the signals supplied to a the pixels PX through the pixel switch SW0
from the signal line S is inversed for two or more pixels PX commonly
connected to a signal line S and arranged adjacent each other along the
signal line S.

[0082]That is, it is a method which makes the polarities of the signals
supplied to the pixel electrodes PE connected to the same signal line S
as follows: positive polarity (+), negative polarity (-), negative
polarity (-), positive polarity (+), positive polarity (+), negative
polarity (-), negative polarity (-), and positive polarity (+) for every
signal line S.

[0083]When yellow color is displayed by this method, the potential of
signal line Sa changes from the potential corresponding to the black
display of positive polarity to the potential corresponding to the white
display of negative polarity during the holding time, further, changes to
the potential corresponding to the black display of negative polarity,
and then changes to the potential corresponding to the white display of
positive polarity

[0084]If a red pixel PXR is observed here, the direct-current (DC)
ingredient of the potential is set off by supplying the potential
corresponding to the white display of positive polarity, and the
potential corresponding to the white display of negative polarity.
Similarly, if a blue pixel PXB is observed, the direct-current (DC)
ingredient of the potential is set off by supplying the potential
corresponding to the black display of positive polarity, and the
potential corresponding to the black display of negative polarity.
Consequently, the average of the direct-current of the signal line
potential is set to about 0 in a total, and a vertical cross talk is
suppressed.

[0085]If the polarity of the pixel electrodes PE connected to a common
signal line S is set off for each color, the effect of the suppression of
the vertical cross talk by such color display can be acquired. Therefore,
the same effect is also obtained by the method of inversing every 3
horizontal periods, every 4 horizontal periods and so on.

[0086]However, a horizontal-stripes pattern of the light and darkness of a
rude pitch may be in sight when the opposite electrode potential shifts
especially in the inversion more than every 3 horizontal periods.
Therefore, the inversion method for every 2 horizontal periods is more
preferred.

[0087]Next, the CCDI driving according to this embodiment is explained.
Since the signal supplied to the pixel electrode PE differs in the
polarity in every column in the CCDI driving, as described above, it is
necessary to divide the connection point of the auxiliary capacitance Cst
with the auxiliary capacitance line Cs into upper and lower auxiliary
capacitance lines Cs with respect to the pixel electrodes PE selected by
the common scanning line G in FIG. 7. The auxiliary capacitance lines Cs
are arranged in parallel with the scanning line G.

[0088]FIG. 7 is a pattern layout of the pixels in case of coupling the
auxiliary capacitance to the pixel electrode PE shown in FIG. 6. For
example, the pixel electrodes PE connected to a common signal line S via
the pixel switch SW0 as shown in FIG. 7 are divided into odd number
columns and even number columns in which the pixel electrodes PE are
arranged. For example, the respective pixel electrodes PE in the odd
number columns (S1, S3, S5, . . . ) are connected to the auxiliary
capacitance lines Cs arranged at upper side of the pixel electrodes PE,
and the respective pixel electrode PE in the even number columns (S2, S4,
S6, . . . ) are connected to the auxiliary capacitance lines Cs arranged
at lower side of the pixel electrodes PE.

[0089]In this case, if the polarity inversion for every 2 horizontal
cycles as shown in FIG. 6 is applied to the above CCDI driving, the
control waveform of the auxiliary capacitance potential becomes
complicated, and the driving by the Cs driver CsD becomes difficult. When
the auxiliary capacitance Cst is arranged as shown in FIG. 7, waveforms
of the scanning line G and the auxiliary capacitance line Cs are shown in
FIG. 8. The gate driver GD successively selects gate lines G1, G2, G3 and
G4 for every 1 horizontal period, then picture signals outputted from the
source driver SD are respectively written into the pixel electrodes PE
arranged in the selected row lines.

[0090]Superposition of the coupling voltage to the pixel electrode PE is
performed by controlling the auxiliary capacitance potential Vc. As shown
in FIG. 8, the coupling voltage changes corresponding to the change of
the auxiliary capacitance potential. That is, at the timing when the
signal writing to the pixel electrode PE is performed, the auxiliary
capacitance potential (Vc1 or Vc2) is applied to the pixel electrode PE
and changes to the (Vc0) for the holding period when a source potential
is held in the pixel electrode PE.

[0091]For example, a picture signal with positive polarity is written into
the red pixel PXR from a signal line Sa-2, which is arranged in a row
line selected by a scanning line Gb-4. Auxiliary capacitance Cst of the
red pixel PXR is connected to a auxiliary capacitance line Csk-4 shown at
the lower side of the pixel electrode PE, and the coupling voltage is
impressed to the pixel electrode PE from the auxiliary capacitance line
Csk-4.

[0092]The potential of the auxiliary capacitance line Csk-4 at the timing
when the scanning line Gb-4 is selected is Vc2, and the potential of the
auxiliary capacitance line Csk-4 at the holding period when the source
potential is held in the pixel electrode PE is Vc0, as shown in FIG. 8.
Therefore, a positive coupling voltage corresponding to the difference
between the potential Vc0 and the potential Vc2 is superposed to the
pixel voltage of the pixel electrode PE

[0093]Similarly, a picture signal with negative polarity is written into
the green pixel PXG from a signal line Sa-1, which is arranged in the row
line selected by the scanning line Gb-4. The auxiliary capacitance Cst of
the green pixel PXG is connected to a auxiliary capacitance line Csk-5
shown at the upper side of the pixel electrode PE, and the coupling
voltage is impressed to the pixel electrode PE from the auxiliary
capacitance line Csk-5.

[0094]The potential of the auxiliary capacitance line Csk-5 at the timing
when the scanning line Gb-4 is selected is Vc1, and the potential of the
auxiliary capacitance line Csk-5 at the holding period when the source
potential is held in the pixel electrode PE is Vc0, as shown in FIG. 8.
Therefore, a negative coupling voltage corresponding to the difference
between the potential Vc0 and the potential Vc1 is superposed to the
pixel voltage of the pixel electrode PE.

[0095]Thus, since the coupling voltage with the same polarity as the
picture signal supplied to pixel electrode PE is impressed to the pixel
electrode PE, the amplitude of the pixel holding voltage is increased.

[0096]Namely, at the timing when the respective scanning lines G are
selected, the potential of the auxiliary capacitance line Cs connected
via auxiliary capacitance Cst to the pixel electrode PE, in which the
signal of positive polarity is supplied, is set to potential Vc2. On the
contrast, the potential of the auxiliary capacitance line Cs connected
via auxiliary capacitance Cst to the pixel electrode PE, in which the
signal of negative polarity is supplied, is set to potential Vc1 in order
to achieve a desired amplitude increase effect. If the potential of each
auxiliary capacitance line Cs is set as mentioned above, the potential
waveform of the auxiliary capacitance line Cs becomes as shown in FIG. 8.

[0097]However, in the potential waveform of the auxiliary capacitance line
Cs as shown in FIG. 8, the potential of the auxiliary capacitance lines
Csk-5, Csk-3, Csk-1 changes among three values (Vc0, Vc1, Vc2). On the
contrast, the potential of the auxiliary capacitance lines Csk-4, Csk-2,
Csk changes between two values. Accordingly, the drive waveform becomes
different by even-numbered auxiliary capacitance lines Cs and
odd-numbered auxiliary capacitance lines Cs.

[0098]In this waveform, since it is necessary to carry out different
driving control between even-numbered auxiliary capacitance lines Cs and
odd-numbered auxiliary capacitance lines Cs, the circuit of Cs driver CsD
is complicated, and which may result in cost up and an increase in frame
area.

[0099]When auxiliary capacitance lines Csk-5, Csk-3, Csk-1 shift from the
first level to the second level, it is necessary to change the potential
from the potential Vc1 to the potential Vc2, or from the potential Vc2
from the potential Vc1. Therefore, if time constant of the auxiliary
capacitance line Cs is large, the potential of the second level may not
be stable within 1 horizontal period. In the case, a difference in
auxiliary capacitance line potential arises between the auxiliary
capacitance lines Csk-5, Csk-3, Csk-1 and the auxiliary capacitance lines
Csk-4, Csk-2, Csk whose potentials do not need to be changed, and which
results in a poor display, such as a horizontal stripe.

[0100]Then, in the liquid crystal display device according to this
embodiment, an auxiliary capacitance Cst is arranged as shown in FIG. 9.
FIG. 9 is a pattern layout of the pixels in case of coupling an auxiliary
capacitances to the pixel electrodes PE shown in FIG. 6 according to a
third embodiment of the present invention.

[0101]In FIG. 9, the pixel electrodes PE lined in a row direction is
arranged so as to be sandwiched by a pair of capacitance lines Cs, that
is, an upper auxiliary capacitance line Cs and a lower auxiliary
capacitance line Cs to supply auxiliary capacitance line voltages of
different polarities, respectively. Namely, the auxiliary capacitance
lines Cs to supply the auxiliary capacitance line voltages of different
voltages are connected to the pixel electrodes PE arranged along a common
signal line S in mixture.

[0102]For example, in the line of pixels PX selected by the scanning line
Gb-4, the pixel electrodes PE to which the picture signals of positive
polarity are written in are connected to the auxiliary capacitance line
Csk-4 arranged at lower side of the pixel electrode PE via the auxiliary
capacitance Cst in FIG. 9.

[0103]Similarly, in the line of pixels PX selected by the scanning line
Gb-4, the pixel electrodes PE to which the picture signals of negative
polarity are written in are connected to the auxiliary capacitance line
Csk-5 arranged at upper side of the pixel electrode PE via the auxiliary
capacitance Cst.

[0104]In the line of pixels PX selected by the scanning line Gb-3, the
pixel electrodes PE to which the picture signals of positive polality are
written in are connected to the auxiliary capacitance line Csk-4 arranged
at upper side of the pixel electrode PE via the auxiliary capacitance
Cst.

[0105]Similarly, in the line of pixels PX selected by the scanning line
Gb-3, the pixel electrode PE to which the picture signals of negative
polality are written in are connected to the auxiliary capacitance line
Csk-3 arranged at lower side of the pixel electrode PE via the auxiliary
capacitance Cst.

[0106]FIG. 10 shows a driving wave chart of the scanning line G and the
auxiliary capacitance line Cs in the case of an arrangement of the
auxiliary capacitance Cst as shown in FIG. 9. In the timing when the
pixels PX are selected by the scanning line G for every line as shown in
FIG. 10, the potential of the auxiliary capacitance line Cs connected to
the pixel electrodes PE in which the signals of positive polarity are
written in, is set to the potential Vc2. Similarly, the potential of the
auxiliary capacitance line Cs connected to the pixel electrodes PE in
which the signals of negative polarity are written in, is set to the
potential Vc1.

[0107]In the driving waveform of the potential of the auxiliary
capacitance line Cs shown in FIG. 10, the potential changes with two
values about all the auxiliary capacitance lines Cs. For example, signals
with negative polarity are written into the pixel electrodes PE connected
to an auxiliary capacitance line Csk-3 via auxiliary capacitance Cs.

[0108]Therefore, it is necessary to superimpose the coupling voltage of a
negative side to the pixel electrodes PE, in the timing when the scanning
line Gb-3 and the scanning line Gb-2 are selected. Namely, the potential
of an auxiliary capacitance line Csk-3 is set to the potential Vc1.

[0109]In the liquid crystal display device according to this embodiment,
the polarity of the picture signals written in the pixel electrode PE is
inversed every two scanning lines G (cycle of four lines). On the
contrary, the polarity of the potential of the auxiliary capacitance line
Cs is inversed in every other line (cycle of two lines).

[0110]If the auxiliary capacitance line Cs is driven as shown in FIG. 10,
the circuit constituting the Cs driver CsD becomes more simple because
all the driving waveforms of the auxiliary capacitance line Cs become two
steps, and the changing cycle becomes the cycle of two lines from the
cycle of four lines. Furthermore, the effect of cost reduction and
reduction of frame area is obtained. A poor display such as a horizontal
stripe resulting from insufficient potential convergence of the auxiliary
capacitance line Cs, can be eliminated.

[0111]Next, the selection driving using a selection circuit MPX in the
liquid crystal display device according to an embodiment is explained
referring to FIG. 11. FIG. 11 shows the display portion and a selection
circuit in case of conducting an alternating driving operation and a
selection driving operation using the pattern layout of the pixels shown
in FIG. 6 according to a fourth embodiment of the present invention.

[0112]FIG. 11 shows the selection circuit MPX which distributes output
signals from one output terminal of the source driver SD to a plurality
of signal lines S in time sharing. In this embodiment, the output signals
from the source driver SD is distributed to 18 signal lines S1-S18, for
example from six output terminals SS (SS0-SS5) of the source driver SD.
FIG. 11 shows the number of signal lines S as 18, in order to explain
easily. However, it is necessary to make the number of signal lines S
change according to resolution of a display.

[0113]The selection circuit MPX is structured so that the output signals
from one output terminal SS of the source driver SD are distributed to a
plurality of pixel PXs to which the signals with the same color and the
same polarity are supplied.

[0114]The control circuit CTR includes a selection drive control means
(not shown) which controls the source driver SD and the selection circuit
MPX so that the same signals are supplied twice or more to at least one
of two or more signal lines S to which the output signals from one output
terminal SS are distributed in 1 horizontal period.

[0115]When selecting the signal lines S of the same color and the same
polarity as a combination of signal lines S selected simultaneously, the
output signals from the source driver SD are distributed as shown in FIG.
11. Here, one example is shown about the case (three line selection
system) where the output signals from one output terminal of the source
driver SD are distributed to three signal lines S. In FIG. 11, although
the scanning lines G1˜G10 are not illustrated, instead, only the
row number is shown. In connection with this, FIG. 11 shows the pixel
switch SW0 in simplified manner.

[0116]For example, when one of the row lines of the pixels PX selected by
a scanning line G1 is observed, the arrangement of the pixels from
left-hand side (the direction of an ascending order of signal lines S) is
follows: Red pixel PXR (R+) of positive polarity, Green pixel PXG of
negative polarity (G-), blue pixel PXB (B+) of positive polarity, Red
pixel PXR of negative polarity (R-), green pixel PXG (G+) of positive
polarity, Blue pixel PXB of negative polarity (B-), Red pixel PXR of
positive polarity (R+), and Green pixel PXG (G-) of negative polarity.
The arrangement is periodic, and a pixel PX of the same color and the
same polarity appears at interval of 6 pixels.

[0117]Therefore, in FIG. 11, output signals from an output terminal SS0 of
the source driver SD is distributed to signal lines S1, S7, and S13.
Similarly, output signals from an output terminal SS1 of the source
driver SD is distributed to signal lines S2, S8, and S14. Thus, the
output signals from one output terminal of the source driver SD are
distributed to signal lines S in every six line. Here, the output from
the output terminal SS1 of the source driver SD is connected to a signal
line S2 via a second switch SW2, is connected to a signal line S8 via a
third switch SW3, and is connected to a signal line S14 via the first
switch SW1, for example. The control of ON and OFF of the first switch
SW1, second switch SW2, and third switch SW3 is carried out by control
signals ASW1, ASW2, and ASW3 from the control circuit CTR.

[0118]The driving method of the liquid crystal display device shown in
FIG. 11 is explained using FIG. 12. The driving method which supplies
picture signals to the pixels PX selected by the scanning lines
G1˜G4 is shown in FIG. 12. In the driving method shown in FIG. 12,
polarity inversion is carried out every two row lines of pixels PX
selected by the scanning line G, and the second row line and the fourth
row line of the pixels PX correspond to starting lines of the polarity
reversion.

[0119]As shown in FIG. 12, in one horizontal period (1H), the first switch
SW1, the second switch SW2, and the third switch SW3 are turned on
simultaneously, and picture signals are written in all the signal lines
S. Next, the first switch SW1 is turned off, then, the second switch SW2
is turned off, and finally the third switch SW3 is turned off.

[0120]In one horizontal period, the ON voltage of the pixel switch SW0 is
supplied to the scanning line G, and the picture signal supplied to the
signal line S from the source driver SD is written in the pixel electrode
PE via the pixel switch SW0. Consequently, the picture signal with a
color and a polarity as shown in FIG. 11 is held at each pixel electrode
PE.

[0121]According to this embodiment, when a pixel switch SW0 connected to
an adjoining signal line S is switched, the influence of stray
capacitance produced between the pixel electrode PE and the adjoining
signal line S can be eliminated. Accordingly, deterioration of the
display quality due to the change of the holding potential of the pixel
electrode PE is suppressed.

[0122]For example, in the line of pixels PX selected by the scanning line
G1, a red pixel PXR connected to the signal line S1 via the pixel switch
SW0, a green pixel PXG connected to the signal line S2 via the pixel
switch SW0 and a blue pixel PXB connected to the signal line S3 via the
pixel switch SW0 are observed.

[0123]First, in the timing of the beginning of 1 horizontal period (1H
(G1)), the first switch SW1 to the third switch SW3 are turned on. At
this time, a picture signal R+ is supplied to the signal line S1, and a
picture signal R+ is written in the pixel electrode PE via the pixel
switch SW0. A picture signal G- is supplied to the signal line S2, and
the picture signal G- is written in the pixel electrode PE of the green
pixel PXG via the pixel switch SW0.

[0124]Once writing operation is performed to the signal line S, the signal
written in pixel electrode is held until the signal line S is selected
again. A parenthesis (G+), (R-) in FIG. 12 shows the signal potential
currently held.

[0125]In a next timing of 1 horizontal period (1H (G1)), the first switch
SW1 is turned off while the second switch SW2 and the third switch SW3
are maintained in the ON state. Therefore, the picture signal (R+) is
held at the pixel electrode PE of the red pixel PXR. The picture signal
(G-) is again supplied to the signal line S2 again, and the picture
signal (G-) is written in the pixel electrode PE of the green pixel PXG
via the pixel switch SW0 again. The picture signal (B+) is supplied to
the signal line S3 again, and the picture signal (B+) is written in the
pixel electrode PE of the blue pixel PXB via the pixel switch SW0 again.

[0126]Here, in the floating state where a signal line S is separated from
the output terminal SS of the source driver SD, if the potential of
adjoining signal line S fluctuates, the potential of the signal line S in
the floating state changes due to the change of the stray (coupling)
capacitance produced between the floating signal line S and the adjoining
signal line S.

[0127]However, in this embodiment, the potential of the signal line S1 is
held and the picture signal (G-) is again written in the signal line S2
adjacent to the signal line S1. Since the same signal as the last time is
written in the signal line S2 and the potential of the signal line S2
does not change, the coupling is not changed between the signal line S1
and the signal line S2.

[0128]Similarly, in the last timing of 1 horizontal period (1H (G1)), the
first switch SW1 and the second switch SW2 are turned off, and the third
switch SW3 is turned on. Therefore, the picture signal (G-) is held at
the pixel electrode PE of the green pixel PXG. A picture signal (B+) is
supplied to the signal line S3, and the picture signal (B+) is written in
the pixel electrode PE of the blue pixel PXB via the pixel switch SW0.

[0129]Here, the potential of signal line S2 is held and the picture signal
(B+) is written in the signal line S3 adjacent to the signal line S2.
However, since the same signal as the last time is written in the signal
line S2 and the potential of the signal line S2 does not change, the
coupling produced between the signal line S2 and the signal line S3 does
not change.

[0130]The polarity of the signals supplied to the signal line S is
inversed between 1 horizontal period (1H (G1)) when the scanning line G1
is selected and 1 horizontal period (1H (G2)) when the scanning line G2
is selected. Thus, in the timing when the polarity of the signals is
inversed, if the time constant of the signal line S is large, time to
write signals in the signal line S becomes long.

[0131]However, as mentioned above, insufficient signal write-in to the
signal line S can be improved by writing the picture signals in the
signal line S a plurality of times, and a liquid crystal display device
having good display quality can be obtained.

[0132]Here, for example, one comparative example is reviewed. In this
example, in 1 horizontal period, the first switch SW1 is turned on, and
then the first switch SW1 is turned off while the second switch SW2 is
turned on, and further the second switch SW2 is turned off while the
third switch SW3 is turned on.

[0133]For example, when the first switch SW1 is turned on in the beginning
of 1 horizontal period (1H (G1)), the output signals from the output
terminals SS0, SS1 and SS2 of the source driver SD, are written in signal
lines S1, S9, and S14.

[0134]When the second switch SW2 is turned on next, the output signals
from the output terminals SS0, SS1, and SS2 of the source driver SD, are
written in signal lines S2, S7, and S15.

[0135]Here, in the floating state where the signal line S is separated
from the output terminal SS of the source driver SD, if a potential of
adjoining signal line S fluctuates, the potential of the signal line S in
a floating state changes with the stray (coupling) capacitance produced
between the adjoining signal lines S and the floating signal lime S. For
example, signal lines S2, S8, and S14 in which the signal of picture
signal G+ is written in 1 horizontal period (1H (G3)), are observed.

[0136]With respect to the signal line S8, since the third switch SW3 is
turned on, and the picture signal G+ is written in the pixel electrode
PE, in the last timing of the 1 horizontal period (1H (G3)), the signal
line 18 does not receive the coupling after that.

[0137]However, with respect to the signal line S2, after the second switch
SW2 is turned on, and the picture signal G+ is written in the signal line
S2, the third switch SW3 is turned on. Accordingly, the potential of the
signal line S3 arranged next changes. The coupling between the signal
line S2 and the signal line S3 changes due to the potential change of the
signal line S3, therefore the potential of the signal line S2 in the
floating state is changed.

[0138]With respect to the signal line S14, after the first switch SW1 is
turned on, and the picture signal G+ is written in the signal line S14,
the second switch SW2 is turned on. Consequently, the potential of the
signal line S15 arranged next changes, and coupling between the signal
line S14 and the signal line S15 changes. Finally the potential of the
signal line S14 changes with the potential change of the signal line S15.
Successively, the third switch SW3 is turned on, and the potential of the
signal line S13 arranged at another next side changes. The coupling
between the signal line S14 and the signal line S13 changes, thereby the
potential of the signal line S14 changes with the potential change of the
signal line S13 again.

[0139]According to above operation, the signal voltages held in the signal
lines S2, S8, and S14 become slightly different from each other.
Consequently, the pixel potential held at the pixel electrodes PE become
also slightly different each other, which results in a pattern of light
and darkness of luminosity, and is recognized visually as a horizontal
stripe or a vertical stripe. This does not become a problem so much, when
the gray display is performed, but when performing color display, such as
yellow, the stripes appear notably.

[0140]On the other hand, if a liquid crystal display device is driven as
shown in FIG. 12, the voltage held a pixel electrode PE cannot be
affected by the influence of the potential change of an adjoining signal
lines S. Therefore, a high quality liquid crystal display device can be
obtained.

[0141]As mentioned above, according to the liquid crystal display device
of this embodiment, it becomes possible to provide a high quality liquid
crystal display device using the delta arrangement of pixels and the
driving method of the same, which results in low power consumption and a
narrow picture frame.

[0142]A liquid crystal display device and a driving method of the same
according to a fifth embodiment of the present invention is explained
below with reference to FIG. 13. FIG. 13 shows a display portion and a
selection circuit in case of conducting the alternating driving operation
and the selection driving operation using the pattern layout of pixels
shown in FIG. 6.

[0143]In the liquid crystal display device according to this embodiment, a
liquid crystal layer includes an OCB mode liquid crystal material to
which the liquid crystal is transferred to a bend alignment state from a
spray alignment state for a display operation of a normally white.
According to this embodiment, the reverse transference from the bend
alignment state to the spray alignment state is prevented by periodically
applying a high driving voltage (hereafter referred to a black insertion
voltage) corresponding to a black display to the liquid crystal layer,
for example, as a non-picture signal.

[0144]The control circuit CTR performs an initialization processing to the
liquid crystal molecule so that the liquid crystal molecule is
transferred to the bend alignment state from the spray alignment state by
applying an comparatively high opposite common voltage Vcom to the liquid
crystal layer at the time of a power ON.

[0145]A combination manner with the signal lines S and the output
terminals SS0-SS5 of the source driver SD according to this embodiment
differs from that of the fourth embodiment as shown in FIG. 11.

[0146]The selection circuit MPX is structured so that the output signal
from one output terminal SS is distributed to the pixel electrodes PE
(PXR, PXG, PXB) to which a plurality of kinds of color picture signals
having the same polarity are supplied respectively.

[0147]The control circuit CTR includes a selection drive control circuit
(not shown) which controls the source driver SD and the selection circuit
MPX to distribute a reset signal to the pixels PX in the first period of
1 horizontal period and supply picture signals to the pixels PX in the
second period of 1 horizontal period.

[0148]In the liquid crystal display device according this embodiment,
three signal lines S corresponding to a red pixel PXR, a green pixel PXG,
and a blue pixel PXB having the same polarity are selected by a set. For
example, the output signal from an output terminal SS0 of the source
driver SD is supplied to signal lines S1, S3, and S5, the output signal
from an output terminal SS1 to signal lines S2, S4, and S6, and the
output signal from output terminal SS2 to signal lines S7, S9, and S11.

[0149]For example, when pixels PX are selected by a scanning line G2, the
output signal from the output terminal SS0 of the source driver SD is
distributed to the signal lines S1, S3, and S5. The picture signal of
negative polarity (G-) supplied to the green pixel PXG is distributed to
the signal line S1, a picture signal (R-) of the negative polarity
supplied to the red PXR is distributed to the signal line S3, and a
picture signal (B-) of the negative polarity supplied to the blue pixel
PXB is distributed to the signal line S5.

[0150]The output signal from the output terminal SS1 of the source driver
SD is distributed to the signal lines S2, S4, and S6. The picture signal
(B+) of the positive polarity supplied to the blue pixel PXB is
distributed to the signal line S2, the picture signal (G+) of the
positive polarity supplied to the green pixel PXG is distributed to the
signal line S4, and the picture signal (R+) of the positive polarity
supplied to the red pixel PXR is distributed to the signal line S6.

[0151]The output signal from the output terminal SS2 of the source driver
SD is distributed to signal lines S7, S9, and S11. The picture signal
(G-) of the negative polarity supplied to the green pixel PXG is
distributed to the signal line S7, the picture signal (R-) of the
negative polarity supplied to the red pixel PXR is distributed to the
signal line S9, and the picture signal (B-) of the negative polarity
supplied to the blue pixel PXB is distributed to the signal line S11.

[0152]As mentioned above, in 1 horizontal period, the signals outputted
from each of the output terminals SS0˜SS5 of the source driver SD
are signals to be supplied to the red pixel, the green pixel, and the
blue pixel of the same polarity respectively. The polarity of the signals
outputted from each of the terminals is inversed for every 2 horizontal
periods.

[0153]In the case of distributing the signals from the output terminals
SS0˜SS5 of the source driver SD to the signal lines S, a driving
timing chart of the liquid crystal display device shown in FIG. 13 is
shown in FIG. 14. A reset signal is written in the pixel in a head timing
of 1 horizontal period. In the liquid crystal display device according
this embodiment, the reset signal corresponds to a black display.

[0154]That is, in the head timing of 1 horizontal period, the first switch
SW1, the second switch SW2, and the third switch SW3 are turned on
simultaneously, and the reset signal is supplied to all the pixel PXs
which the scanning line G selects.

[0155]After the writing of the reset signal, signals from the respective
output terminals SS0˜SS5 of the source driver SD are outputted in
an order of the picture signal (R+ or R-) to the red pixel PXR, the
picture signal (G+ or G-) to the green pixel PXG, and the picture signal
(B+ or B-) to the blue pixel PXB. On the other hand, the turn that the
first switch SW1, the second switch SW2, and the third switch SW3 is
turned on is not necessarily the same for each horizontal period (1H).

[0156]A potential change of the signal line S is explained at the time of
driving the above-mentioned liquid crystal display device. For example,
if 1 horizontal period (1H (G2)) is observed, as shown in FIG. 14, a
reset signal K+ or a reset signal K- is written in the signal line S
corresponding to the output terminals SS0˜SS5 of the source driver
SD, when the first switch SW1, the second switch SW2, and the third
switch SW3 are turned on simultaneously.

[0157]For example, the reset signal K- is written in the signal lines S1,
S3, and S5 from the output terminal SS0, and the reset signal K+ is
written in the signal line S2, S4, and S6 from the output terminal SS1.
Next, the third switch SW3 is turned on and corresponding signal lines
S3, S6 . . . become in a selected state. At this time, a picture signal
(R-) of the negative polarity supplied to the red pixel PXR is written in
the signal line S3 from the output terminal SS0, and a picture signal
(R+) of the positive polarity supplied to the red pixel PXR from the
output terminal SS1 is written in the signal line S6.

[0158]Next, the first switch SW1 is turned on, and corresponding signal
lines S1, S4 . . . become in a selected state. At this time, the picture
signal (G-) of the negative polarity supplied to the green pixel PXG is
written in the signal line S1 from the output terminal SS0, and the
picture signal (G+) of the positive polarity supplied to the green pixel
PXG from the output terminal SS1 is written in the signal line S4.

[0159]Finally, the second switch SW2 is turned on and corresponding signal
lines S2, S5 . . . become in a selected state. At this time, the picture
signal (B-) of the negative polarity supplied to blue pixel PXB is
written in the signal line S5 from output terminal SS0, and the picture
signal (B+) of the positive polarity supplied to the blue pixel PXB from
the output terminal SS1 is written in the signal line S2.

[0160]In 1 horizontal period (1H (G2)), since the voltage of the scanning
line G2 is ON voltage Vgon as shown in FIG. 13, the picture signal having
a desired color and a desired polarity is written in the pixel PX where
the scanning line G2 selects. In other 1 horizontal period, picture
signals are similarly supplied to the pixels PX. Although FIG. 14 shows a
part of period when an ON voltage Vgon is supplied to the scanning lines
G1˜G4, the scanning lines G are also driven as shown FIG. 14 for
other periods (not illustrated).

[0161]In FIG. 14, when writing of a picture signal and a reset signal is
performed to a certain signal line S, and the potential of the signal
line S is changed, influence of the coupling by the potential change of
the certain signal line S is given to a liquid crystal capacitance of
pixels PX arranged adjacently. An arrow shows a portion where the
influence is given. In the timing when the potential of the certain
signal line S changes, the arrow is directed toward a signal line S side
affected by the influence of the potential change of the certain signal
line S.

[0162]For example, when only the second switch SW2 is selected in a 1
horizontal period (1H (G2)) period, writing is performed to the signal
line S2, and the potential of the signal line S2 is changed from the
reset signal K+ of positive polarity to the picture signal B+
corresponding to the blue display of positive polarity. Since the change
of the potential gives influence of coupling to adjoining signal lines S1
and S3 at this time, the influence is shown by the arrow.

[0163]However, even if coupling arises, when writing is performed again in
a sequence within 1 horizontal period, the influence of coupling is not
displayed because the influence is balanced. For example, when only the
third switch SW3 is selected in a 1 horizontal period (1H (G2)), writing
is performed to the signal line S3, and the potential of the signal line
S3 is changed from the reset signal K- of negative polarity to the
picture signal R- corresponding to the red display of negative polarity.

[0164]The change of the potential of the signal line 3 gives an influence
of coupling to adjoining signal lines S2 and S4. However, afterward, the
second switch SW2 is selected, and a picture signal B+ corresponding to
the blue display of positive polarity is written in the signal line S2.
Furthermore, the first switch SW1 is selected, and the picture signal G+
corresponding to the green display of positive polarity is written in the
signal line S4. Therefore, the influence of coupling by the potential
change of signal line S3 is lost.

[0165]As mentioned above, if the voltage of the signal lines S shifts
slightly due to the influence of the coupling, the voltage is also
written in the pixel electrode PE connected to the signal line S.
Consequently, the shifted voltage is held in each pixel electrode PE.

[0166]When reviewing what kind of coupling each signal line S receives in
whole 1H period in case of writing picture signals in the pixel electrode
PE in FIG. 13, the result for all the signal lines S is as follows.

[0167]Namely, a signal line S in which the picture signal R+ corresponding
to the red display of positive polarity was written in is affected by an
influence of the potential change of adjoining signal lines S, such as
the reset signal K- to the picture signal G- corresponding to the green
display of negative polarity, and the reset signal K- to the picture
signal B- corresponding to the blue display of negative polarity.

[0168]A signal line S in which the picture signal R- corresponding to the
red display of negative polarity was written in is affected by an
influence of the potential change of adjoining signal lines S, such as
the reset signal K+ to picture signal G+ corresponding to the green
display of positive polarity, and the reset signal K+ to the picture
signal B+ corresponding to the blue display of positive polarity.

[0169]A signal line S in which the picture signal G+ corresponding to the
green display device of positive polarity was written in is affected by
an influence of the potential change from the reset signal K- to the
picture signal B- corresponding to the blue display of negative polarity.

[0170]A signal line S in which the picture signal G- corresponding to the
green display device of negative polarity was written in is affected by
an influence of the potential change of the adjoining signal line S, such
as the reset signal K+ to the picture signal B+ corresponding to the blue
display of positive polarity.

[0171]Signal line S in which a picture signal B+ corresponding to the blue
display device of positive polarity was written in is not affected by the
influence of the potential change of adjoining signal line S. Similarly,
a picture signal B- corresponding to the blue display of negative
polarity is not also affected by the influence of the potential change of
adjoining signal line S.

[0172]As mentioned above, the potential change by which the written
picture signals are influenced is common for the written picture signals
with the same color and the same polarity.

[0173]When the polarity inversion of the signals supplied to the pixel
electrodes PE is carried out for every one frame, the writing of the
signal corresponding to the red display of positive polarity and the
signal corresponding to the red display of negative polarity are inversed
for every one frame period, for example. That is, the influence of the
potential change is balanced for the signal lines S and the pixel
electrodes PE in which the picture signals corresponding to all the red
displays are written.

[0174]Therefore, in case of where all the pixels display single color,
even if the holding potential slightly shifts under the influence of the
potential change of adjacent signal lines S, the amount of the potential
shift is the same for the whole display area. Accordingly, a vertical
stripe and a horizontal stripe do not arise and a uniform display can be
obtained. This is the same not only in a gray and a monochrome (red,
blue, green) display but in all the displays, including other colors such
as yellow, cyan, and magenta.

[0175]The above effects are acquired, if an order of the signal writing in
each horizontal period as follows: in an order of the reset signal K+ of
positive polarity, the picture signal R+ corresponding to the red
display, the picture signal G+ corresponding to the green display and the
picture signal B+ corresponding to the blue display, or in an order of
the reset signal K- of negative polarity, the picture signal R-
corresponding to the red display, the picture signal G- corresponding to
green display, and the picture signal B- corresponding to the blue
display.

[0176]In FIG. 13, the set of the signal lines S that are distributed from
one output terminal SS of the source driver SD, is constituted by the
picture signal R corresponding to the red display, the picture signal G
corresponding to the green display, and the picture signal B
corresponding to the blue display, which have the same polarity,
respectively. However, the set may be constituted by adjacent three
signal lines S.

[0177]Although this embodiment explains the case where the source driver
SD outputs the picture signals within 1 horizontal period in a following
order: the picture signal R corresponding to the red display, the picture
signal G corresponding to the green display, and the picture signal B
corresponding to the blue display having the same polarity, respectively.
However, following another order is applicable: the signal G
corresponding to the green display, the picture signal R corresponding to
the red display, and the picture signal B corresponding to the blue
display having the same polarity, respectively. Further following other
order is also applicable: the picture signal B corresponding to the blue
display, the picture signal G corresponding to the green display and the
picture signal R corresponding to the red display, respectively in the
liquid crystal display device according to this embodiment.

[0178]As long as reset signals K+ and K- are fixed voltages in a full
screen, the voltage value may be arbitrarily decided. In this embodiment,
although the reset signals K+ and K- are the voltages corresponding to a
black display, they may be the voltages corresponding to a white display,
for example.

[0179]Although the reset signals K+ and K- are set to a common fixed
voltage for a red pixel PXR, a green pixel PXG, and a blue pixel PXB, the
reset signals K+ and K- may be set to different voltage value for every
color pixels.

[0180]For example, the period when the reset signal is divided into three
subperiods, and further the respective voltage values outputted from the
source driver SD are slightly changed. Accordingly, slightly different
reset voltages K+ and K- can be respectively supplied to the signal lines
S connected to the red pixel PXR, the green pixel PXG, and the blue pixel
PXB. According to the above embodiment, a uniform display device and a
driving method using the same without a vertical stripe and a horizontal
stripe are obtained like the preceded embodiments.

[0181]By the way, a black insertion drive is known as a driving method of
a liquid crystal display device. In the driving method, a black display
is inserted in a predetermined ratio during one frame period to improve
visibility of moving pictures. In order to perform a black insertion
driving, an OCB liquid crystal having a high speed response is used well.
On the other hand, in the OCB mode liquid crystal, it is known that the
black insertion driving is also suitable to prevent a reverse
transference.

[0182]In the black insertion drive, it is necessary to perform two signal
writings of the color signals and the picture signal corresponding to the
black display within one frame period. The driving timing shown in FIG.
14 is very suitable for the black insertion drive.

[0183]That is, the black insertion driving is realized by dividing 1
horizontal period into the first period (reset signals K+, K- writing)
and the second period (picture signals R±, G±, B± writing)
following the first period, and using the reset signals K+ and K- as the
black insertion signals.

[0184]FIG. 15 shows a timing chart including potential of the scanning
line G according to a sixth embodiment. The black color signal write-in
scan is performed to lines GN+1˜GN+6 using the first period of 1
horizontal period (1H), that is, only corresponding period to write-in
the reset signal K+, or the reset signal K-. Furthermore, the picture
signal write-in scan is performed in the scan lines G1˜G6 using
only the second period of 1 horizontal period (1H), i.e., a period
corresponding to write the picture signals R±, G±, and B±.

[0185]As mentioned above, since the driving timing shown in FIG. 14 can be
combined with the black insertion driving, visibility of the moving
pictures can be improved. Accordingly, while the same effect as the
preceding embodiments is obtained, it also becomes possible to raise the
visibility of the moving pictures.

[0186]The present invention is not limited directly to the above described
embodiments. In practice, the structural elements can be modified without
departing from the spirit of the invention. Various inventions can be
made by properly combining the structural elements disclosed in the
embodiments. For example, some structural elements may be omitted from
all the structural elements disclosed in the embodiments. Furthermore,
structural elements in different embodiments may properly be combined. It
is to therefore be understood that within the scope of the appended
claims, the present invention may be practiced other than as specifically
disclosed herein.